I had similar problems with one of my optical drives, it wouldnt read the cd correctly. SO i made a plain and ordinarly copy of that CD (you cannot play with a copy, but it installs fine from a coppied cd).
It may be that either the cd rom is failing (as mentioned) or that the lazer is getting durty, or that the lazer is just getting weak
(it happens unfortunately - if you ever had the fun of working with your 4-12x cd roms, remember how the first ones battled to read coppied cd's? mainly because coppied ones were dark blue , where as originals were silver and the lazer was too weak to reflect off the blue. Today's writables is a light greenish colour, which for some weird reason reflect the lazer better than silver)
But yes, whereever you bought the game from, they normally dont have too much hassles replacing the game. (they should only have hassles if you want to replace it with another game - which a lot of people do when they have already coppied and "patched" the game)
Hope you get this one solved without any headaches. <img src="/ubbthreads/images/graemlins/wave.gif" alt="" />
